Tuesday, January 12, 2010

Stains in the furniture finishing

Stain is the finishing material that determines the color of the final finishing. About the types of stain you can view in my previous article: the stain for wood finishing. Meanwhile, in this post we will discuss about stain according to its application. Here will discuss about the stains according to their function in the process of finishing furniture. According to the usage purpose, stain can be classified into: sap stain, equalizer stain, body stain, glaze and pad stain.

wood variation in the basic color

Sap stain and equalizer stain

Now most of furniture manufacturer are getting more difficult to get the good wood as raw materials. The wood more difficult to be sourced and more expensive in price. This situation force the furniture manufacturer to source the cheaper wood and accept the lower grade of wood. There many problem can come since this choice. One of the problems often encountered in the furniture production is the basic color of the wood that varies in every place and every time. Meanwhile the demand to the furniture product quality is getting higher and finishing color need to be uniform to all furniture product. In other side the wood color become more varies. Therefore, to overcome the variation of the basic colors of wood, the finishing process almost always required stain application to make even and uniform color. To help uniform the color we can adjust the wood base color at the beginning of the finishing process using a special stain, the sap stain and equalizer stain.

Sap stain is a stain that is used to bring the light color of the wood to the dark color. Sap stain mostly is brown color usually used to cover the light-colored wood. While equalizer stains work in the opposite with the sap stain. The equalizer stain is stain used to cover and camouflage the striking color of wood in certain parts that will disturbing the final finishing color. The color of sap stain and equalizer stain is depending on the basic color of wood and the final color of the finishing desired. The most widely used equalizer stain is equalizer with green color stain to tone down the red colors in the wood. But actually we can make sap stain and equalizer stain in every color.

Body Stain

The body stain is a stain that is applied evenly to overall surfaces. Body stain is the main stain used to build the color to bring the wood from its color to the desired finish color. The selection of the body stain color and type, mainly depends on the color of the wood and the final finishing color and looked. Now mostly the body stain is applied by spray. Other applications method such as: brushed, dipped, wipe is also can be used, but become rarely because the finishing speed and quality reason. For specific colors, especially dark color, sometimes we need to apply the stain 2 times or even more, either with the same or different type of stain.

Pad Stain

Pad stain is a special type of stain which can be applied on sealer or top coat by padding. Pad stain is made from organic pigments (dye) with alcohol solvent. With alcohol as the solvent, the pad stain can be applied over sealer or top coat without bite too much. The dye pigment, make it won’t cover too much and keep the clarity of the finishing color. If the application of pad stain is considered too much or too thick, it can be removed again by rub with steel wool or sandpaper without too much damage to the existing finishing underneath. The pad stain is also available to make a variety of finishing effects such as: antique effects, dirty effect, burnish (dark color) on the corners, spatter, watermark etc.).

Pad stain is also used to even the color before the last top coat. to make the uniform color before the last top coat. For this purpose, pad stain is mostly applied by spray. Many finishing peoples like to adjust the finishing color in this step, because the color is more clearly viewed. The finishing color can be viewed and adjusted after the sealer or top coat application. In the stain and glaze application step, the finishing color is difficult to be viewed.

But we need to note that the addition colors over top coat or sealer should be minimize as much as possible. The application too much stain on the sealer or top coat will block and cover the grain and reduce the live and beauty of the grain looked.

Glaze.

Glaze is a kind of wiping stain, the stain that his application requires process of wiping. More about this glaze can be seen on my other article: glaze for wood finishing. In an antique finish, glaze is normally used to make antic effects to produce the special appearance such as: dirty, dusty or other effect that necessary. However this glaze can also be used to form the color of the finishing process. Use of glaze to form color will make different finishing looked instead of the stain. To produce the desired finish appearance, sometimes we need to apply glaze 2 x. With a good highlight and the proper application the coloring using glaze will produce a soft, alive, interesting and rich looked finishing color. Glaze also can be used to create contrast effect in finishing. The contrast effect is made by contrasting the color of glaze with overall color of finishing, for example: white glaze color over the dark brown finish or black glaze over white color finishing. This method will result an interesting contrast color between the color finishing with color in the inside part such as: groove, inside of carving, grain, and pores.

Glaze application method is by sprayed, poured, or dipped and then wiped with a cloth and brushed to even the layer of the glaze on the surface. By this application, the glaze can easily color and fill in the gaps, groove or inside the carving. Glaze is also designed so it can be added or removed easily without damage the sealer or top coat underneath. So it can be easily added and remove according to the need.